It's the non-Di, though I saw after I could have gotten the Di on KEH for around the same price. Still, no regrets so far -- this thing is gorgeous.

But I did seem to have a problem in the first few minutes with the AF motor really struggling to move. I may have done something with the hood that was blocking the focus ring somehow ... I'm really not sure. Need to keep an eye on it in testing over the next few days. Seems fine now.

I too had the 172E, very light lens which is a good thing. IIRC, the focus ring is push/pull type to switch between MF and AF, so that may have been the issue.